As a programmer of apps and widgets I only need to know the rules of the game that my framework and language exposes, and I think it probably always helps to have a bigger context, but I think it is increasingly less necessary for getting stuff done.
With quantum, the entire stack is different. Like a computer from an alternate universe ;) So that whole stack has to be built up again.
But I think abstraction and encapsulation is going to allow many (most?) programmers to use the quantum computer without ever having to know what's going on behind the keyboard and the screen, just like our normal computers now.
I agree, I tried looking into some QC stuff that was presented that way, my impression after was that it's more akin to learning to solder together PCB boards to make a computer from scratch when all you know is basic HTML.
I think you misunderstand me; I think it's great that people get into QC, and indeed they don't have to know everything from top to bottom (like I don't).
I just think that it should be regarded as getting into a specific area of biology, physics, or any other area of science, instead of being equated to learning C when you know Java, or something :)